Jump to content

Air Frustration


alcoon61
 Share

Recommended Posts

Well not sure what I have gotten into here. I have gone from a freightliner mechanic to a Mack mechanic. My air dryer is blowing off every minute and 40 seconds or so. No noticeable leaks. Replaced the governor today. Nothing changed. After a lot of reading I am suspecting a problem with the unloader valve. I think this is a wabco compressor but not sure. How hard is it to repair the unloader in these? Cant find much literature on these like bendix has. I am getting a lot of water from the air tanks daily when I drain them. I checked the power to the dryer and have 14 volts. I omhed the two prongs on the dryer and could not get a reading at all. Does this mean the heater element is bad?

Mack does a good job of painting over id labels and etc to make sure you come to mack for parts. If anybody has a source to look up by vin please send me the part numbers and make for the dryer and compressor. The last six of the vin is 014310.

I know I sure would like to put my foot in the seat of the pants of the engineer at mack that dreamed up putting the dryer directly under the bunk on the frame a foot or so below my pillow. "Nothing but genuius" Sounds like a rifle when it goes off.

Any other suggestion or help with chasing down a solution would be greatly appreciated.

Thanks,

Andy

Link to comment
Share on other sites

Well not sure what I have gotten into here. I have gone from a freightliner mechanic to a Mack mechanic. My air dryer is blowing off every minute and 40 seconds or so. No noticeable leaks. Replaced the governor today. Nothing changed. After a lot of reading I am suspecting a problem with the unloader valve. I think this is a wabco compressor but not sure. How hard is it to repair the unloader in these? Cant find much literature on these like bendix has. I am getting a lot of water from the air tanks daily when I drain them. I checked the power to the dryer and have 14 volts. I omhed the two prongs on the dryer and could not get a reading at all. Does this mean the heater element is bad?

Mack does a good job of painting over id labels and etc to make sure you come to mack for parts. If anybody has a source to look up by vin please send me the part numbers and make for the dryer and compressor. The last six of the vin is 014310.

I know I sure would like to put my foot in the seat of the pants of the engineer at mack that dreamed up putting the dryer directly under the bunk on the frame a foot or so below my pillow. "Nothing but genuius" Sounds like a rifle when it goes off.

Any other suggestion or help with chasing down a solution would be greatly appreciated.

Thanks,

Andy

Link to comment
Share on other sites

You do have a Wabco compresssor and a Bendix AD9 air dryer on your truck. The Wabco compressors did have problems with their valves getting gummed up with carbon/sludge but this usually caused the compressor not to build up air or build up slowly. We had alot of Pilgiram Pride chicken trucks have this problem and had to replace the compressor head with a new updated head. Although I never remember it affecting the air dryer operation.

Link to comment
Share on other sites

  • 1 month later...

Found cause. Pinhole in signal line near compressor. Plastic lines running unprotected and tie wrapped to the frame and had worn a flat spot on one side and eventually a hole. Another mack engineering booboo. 2 quick connects and a 6 inch piece of line to repair. Cost $11.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...